Fix mixed usage of _

* all modules are using function of _ from oslo.i18n
* remove the definition of _ from openstack.common.__init__.py for safety

Change-Id: Ice2f8be1190fd13e8991a8c7fa55ca636341e875
Closes-Bug: #1382476
Disable name support for lb-healthmonitor-* commands

LBaaS healthmonitor object doesn't have name attribute so
name support should be removed from corresponding commands

Change-Id: I8b45ad5dfdbf6de46ff0a428aaf4cfda8b9f2f95
Closes-Bug: #1387506
Merge "Disable name support for lb-healthmonitor-* commands"
Merge "Fix mixed usage of _"